Episode Synopsis: With Christmas fast approaching, Barney tells Ted that he plans on proposing to Patrice, which leads Ted to debate whether or not to tell Robin. Meanwhile, Marshall and Lily run into an acquaintance from college, on a special one-hour episode of HOW I MET YOUR MOTHER, Monday, Dec. 17 (8:00-9:00 PM, ET/PT) on the CBS Television Network. Seth Green (“Buffy the Vampire Slayer”) guest stars as Daryl LaCorte, Marshall and Lily’s acquaintance in college, and Peter Gallagher (“The OC”) guest stars as Ted’s former architecture professor. Read More...